Snyder is basically saying, that he intended for another Superman movie with kryptonite being sent to Bruce Wayne at the end of it, but because he mentioned Supes fighting Bats for fun at a meeting...that it's now Batman vs Superman. All because WB cant wait for money. They saw the concept and ran with it right away instead of waiting. Not saying it's wrong but now it's a fact.

Like who sent the Kryptonite to Bruce? Lex? That's something that did happen in Lex Luthor: Man of Steel.